President Donald Trump may be doing his darnedest to undermine an investigation of his campaign's alleged ties to the Russian government, but his Department of Justice isn't backing off its pursuit of a Kremlin-backed Ukrainian oligarch.

Firtash has long argued that his 2014 arrest for allegedly running an international titanium racket involving Chicago-based Boeing was politically-motivated, claiming that the Obama administration was using him to punish Russian President Vladimir Putin for annexing Crimea from Ukraine.

Currently free on bail in Austria after posting a $174 million bond, Firtash assembled an all-star team of U.S. lawyers including Clinton White House counsel Lanny Davis, former Homeland Security Secretary Michael Chertoff and former U.S. Attorney Dan Webb. Webb in May urged U.S. District Court Judge Rebecca Pallmeyerto toss the case before Firtash is even brought to Chicago.

Politicos in D.C. and Chicago are closely watching the case to see how aggressively it is prosecuted under the Trump administration. Firtash's business dealings with Manafort — outlined in a separate civil case in New York — may be of interest to federal investigators probing ties between Russia and the Trump campaign.

So far, prosecutors in Chicago aren't backing off. They filed a whopping 115-page brief this week arguing that Firtash should be made to face justice in a Loop courtroom before he can try to have the case thrown out.

Comparing Firtash's racket to the Mafia, prosecutors wrote, "Firtash and (his co-defendant Andras) Knopp have been identified by United States law enforcement as two upper-echelon associates of Russian organized crime; their prosecution will disrupt this organized crime group and prevent it from taking further criminal acts within the United States.

They added, "this prosecution also takes aim at the corruption of foreign public officials, a concern that the Congress has identified as a threat to global security."